The present invention generally relates to an apparatus and method for the continuous input or output of digital data which inputs pictures, audio, text and other large amounts of data so as to effect preserving, editing and, manipulating operations for outputting them.
In the present information society, an extensive amount of information exists in various forms. Especially, information such as pictures, audio and text is offered to the public in the forms of broadcasts, newspapers, publications, records and so on. Retrieval of particular information from among the such large amounts of information is a substantial problem.
Substantial developments in computers and their peripheral apparatuses have made it possible to edit, process and store large amounts of information at higher speeds. Apparatuses for processing and storing the information are now smaller in size, lower in price and higher in performance and the cost of the processing operation has been considerably reduced. However, the picture and audio information is fundamentally analog. When such analog information is digitized, the information amount increases substantially thus requiring a storing apparatus of extremely large capacity to process the information. For example, in picture information, 64K bytes are required if 360.times.240 picture elements and 64 colors are used per picture frame. If the color resolution is improved, several hundreds of K bytes are required. Also, in audio information, for a five second audio output, 100K bytes of information is required at quantization bit and 20 KHz sampling frequency. Furthermore, for moving picture and audio information, the information amount is even more. In order to effect a reproducing operation, the outputting operation must be effected in the real time, and an input/output apparatus is necessary having a large capacity storing apparatus capable of time synchronization at a high speed.
In recent years, with the utilization of the mass fixed disk drives and the optical disks capable of recording and reproducing operations, in addition to development of the data and signal compression of various types of picture and audio signals, a large capacity storing apparatus for digitally recording moving picture and audio information has been realized. FIG. 10 shows a block diagram of an information input/output apparatus using such a large capacity apparatus.
In FIG. 10, reference numeral 35 is a mass memory medium capable of recording and reproducing digital information. Reference numeral 36 is a memory medium controlling device which is adapted to control the information input/output to and from the memory medium 35. Reference numeral 37 is a picture input/output device for effecting the mutual conversion from analog picture information to digital picture information and visa versa. Reference numeral 38 is an audio input/output device for effecting conversion from analog audio information to digital audio information and visa versa. Reference numeral 39 is a master controlling device for controlling the memory media controlling device 36, the picture input/output device 37, and the audio input/output device 38. Reference numeral 40 is an operation means for inputting control commands to the master controlling device 39. The information input/output apparatus of FIG. 10 makes it possible to record and reproduce the continuous picture and audio data.
However, it is difficult to edit the continuously recorded information and to reproduce the results in real time. In a case where the recording operation is effected in a separate area, the actual transfer speed of the storage media (such as a fixed disk drive or an optical disk) becomes slower as compared with a case where the recording and reproducing operations are effected in continuous areas. In order to effect a real time reproducing operation, the recording operation must be effected in continuous areas. Information which has not been continued in the area due to editing cannot be reproduced in real time. Therefore, the edited results must necessarily be copied into other continuous areas to effect the reproducing operation in real time. The storage capacity thus becomes wasted, and also the copying time becomes necessary to therefore increase the duration of the editing operation.